Exploration, development, structural geology

Abstract CO2 injection in depleted oil and gas reservoirs has become increasingly important as a means of mitigating greenhouse gas emissions. This study investigates coupled multiphysics simulations of CO2 injection in chalk reservoirs to better understand the complex thermo-hydro-mechanical-chemical (THMC) processes involved. Two compositional models are created: an isothermal model and a non-isothermal model. Since temperature impacts on fluid compositions have introduced errors in estimating the reservoir's compositions, we made certain simplifications on fluid compositions for the thermal model to address this issue. By using the simplified model, we simulate the temperature propagation of cold fluid into a hot reservoir to observe induced thermal stress due to temperature changes. Despite these simplifications for geomechanical modeling, the propagation of CO2 in the depleted gas reservoir was calculated without considering thermal effects, assuming that the density and viscosity of CO2 remained constant with temperature change in the coupled simulation. Our findings provide valuable insights into the THMC processes involved in CO2 injection in the depleted gas reservoir and highlight the importance of accurately modeling thermal effects to improve simulation accuracy.

doi: 10.2118/214449-MS

SPE EuropEC - Europe Energy Conference featured at the 84th EAGE Annual Conference & Exhibition

SPE-214449-MS

Country:

Europe > Norway > North Sea (1.00)
Europe > Denmark (1.00)

Genre:

Overview (0.48)
Research Report > New Finding (0.35)

Geologic Time:

Phanerozoic > Mesozoic (0.68)
Phanerozoic > Cenozoic (0.46)

Geophysics: Geophysics (0.68)

Industry: Energy > Oil & Gas > Upstream (1.00)

Oilfield Places:

Europe > United Kingdom > North Sea > North Sea > Northern North Sea > Balder Formation (0.99)
Europe > United Kingdom > North Sea > Central North Sea > Utsira High > PL 006 > Ekofisk Formation (0.99)
Europe > United Kingdom > North Sea > Central North Sea > Northern North Sea > Balder Formation (0.99)
(7 more...)

SPE Disciplines:

Reservoir Description and Dynamics > Storage Reservoir Engineering > CO2 capture and sequestration (1.00)
Reservoir Description and Dynamics > Reservoir Simulation (1.00)
Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (1.00)
(4 more...)

Technology: Information Technology (0.70)

Viscoplastic Deformation During CO2 Storage in Danish Chalk Reservoirs: Role of Petrophysical Heterogeneity and Mechanical Alteration

Amour, Frédéric (DTU Offshore) | Hosseinzadehsadati, Seyedbehzad (DTU Offshore) | Nick, Hamidreza M. (DTU Offshore)

Abstract Denmark aims at a 70% reduction in greenhouse gas emissions by 2030 compared to levels measured in 1990, with a long-term target of becoming carbon-neutral by 2050. As part of this national effort, the Bifrost project, aims at repurposing two depleted gas fields in the Danish North Sea for CO2 storage, namely the Harald West sandstone field as the primary target and the neighboring Harald East chalk field as a potential upside. The Harald East chalk is the focus of this study. The storage potential and infrastructures available within the multiple chalk fields located in the Danish North Sea represent valuable assets to fulfill the national objectives enabling a time- and cost-efficient implementation of carbon storage activities. One of the main challenges for carbon storage in chalk is the contradictory experimental results reported in literature that indicate both a strengthening and a softening effect of supercritical CO2 on the plastic and elastic properties of chalk. Such uncertainty hampers accurate prediction of the deformation response of storage sites. In this context, the study aims at assessing the impacts of two levels of uncertainty; the type of mechanical alteration induced by supercritical CO2 and the petrophysical heterogeneity on the long-term deformation behaviour of chalk reservoirs. An in-house hydro-mechanical-chemical model calibrated against experimental data on chalk is applied in a reservoir model of the Harald East field. A 16 year-long injection period is simulated assuming two scenarios. In scenario 1, supercritical CO2 has no impact on the mechanical properties of the rock, whereas in scenario 2, a 30% and 25% lowering of the pore collapse stress and elastic modulus of chalk is assumed. A systematic comparison of the flow and mechanical behaviour of low and high porosity cells located in the vicinity of an injection well indicates that the impact of CO2 on the mechanical properties of chalk, the distance of the cells from the injector, the local stress redistribution taking place in the reservoir between mechanically soft and strong cells, and the presence of natural gas in pore space before CO2 injection are key factors controlling the amount and distribution of plastic deformation occurring in the storage site. The outcome of this work enables quantifying the main risks associated with rock compaction close to and further away from injectors during and after carbon storage in chalk fields.

doi: 10.2118/214399-MS

SPE EuropEC - Europe Energy Conference featured at the 84th EAGE Annual Conference & Exhibition

SPE-214399-MS

Country: Europe > Denmark > North Sea (1.00)

Genre: Research Report (0.69)

Geophysics: Geophysics > Seismic Surveying (0.46)

Industry: Energy > Oil & Gas > Upstream (1.00)

Oilfield Places:

Europe > Norway > North Sea > Central North Sea > Central Graben > Block 2/8 > Valhall Field > Tor Formation (0.99)
Europe > Norway > North Sea > Central North Sea > Central Graben > Block 2/8 > Valhall Field > Hod Formation (0.99)
Europe > Norway > North Sea > Central North Sea > Central Graben > Block 2/11 > Valhall Field > Tor Formation (0.99)
(15 more...)

SPE Disciplines:

Reservoir Description and Dynamics > Storage Reservoir Engineering > CO2 capture and sequestration (1.00)
Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
Health, Safety, Environment & Sustainability > Environment > Climate change (1.00)

Technology: Information Technology (0.68)

Chasing Gas Asset Value Maximization: An Integrated Workflow Led by Reservoir Monitoring

Abstract Currently the oil and gas industry is becoming more digitalized. The abundance of data varieties that are recorded has driven the industry to move forward from the conventional data management to more fashioned data acquisition. The field under study (Field A) is a deep-water gas asset, characterized by a complex internal architecture of many separate and discrete gas charged stacked sand bodies. Objective of this paper is to show the key role of the reservoir monitoring strategy, fully integrated in a multidisciplinary workflow that allowed to detail the reservoir conceptual model leading to the identification of valuable production optimization opportunities. Field A produces through smart wells with selective completions, equipped with permanent down hole gauge (one for each open layer) allowing Real Time Monitoring of the key dynamic parameters (e.g., rate, flowing bottom hole pressure) and implementation of surveillance actions such as selective Pressure Transient Analysis. A workflow is implemented to be able to describe each open layer performance integrating all available data starting from well back allocation verification through virtual metering implementation. Then, Inflow Performance Relationship per layer is used to back-allocate well production to each unit. Robust continuous update of material balance analysis for each layer allowed to verify alignment between the geological gas volume in place and the dynamic connected volume, leading to update coherently also the dynamic model. Comparison between geological gas volume in place and dynamic connected one triggered a revision of geological modelling, reviewing seismic uncertainty and facies modelling, trying to embed dynamic evidence. Among parameters taken in account, layers internal connectivity resulted as the most impacting one. The revised model allowed to identify and rank residual opportunities on developed layers and possible additional explorative targets. The result of this screening led to the strategic business decision to plan an infilling well, with primary target the best unexploited sub-portion identified inside one of the analyzed layers together with other stacked minor targets. The expectation of primary target resulted confirmed by the data acquired in the new well drilled. Moreover, the real time monitoring workflow has been implemented in a digital environment for continuous automated update resulting in continuous reservoir monitoring and management. The successful experience on Field A proved the key role of a structured Reservoir Monitoring strategy as "drive mechanism" for a decision-making process extremely impacting on the core business. The automation of data extraction, will lead the way to an increasingly efficient use of "big amount" of data coming from real time monitoring, thus further improving the overall process of asset maximization opportunities identification.

doi: 10.2118/214397-MS

SPE EuropEC - Europe Energy Conference featured at the 84th EAGE Annual Conference & Exhibition

SPE-214397-MS

Country:

North America > United States (0.28)
Europe > Austria (0.28)

Geophysics: Geophysics > Seismic Surveying > Seismic Interpretation > Seismic Reservoir Characterization (0.46)

Industry: Energy > Oil & Gas > Upstream (1.00)

SPE Disciplines:

Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
Reservoir Description and Dynamics > Reservoir Characterization > Geologic modeling (1.00)
Reservoir Description and Dynamics > Formation Evaluation & Management > Well performance, inflow performance (1.00)
(5 more...)

Technology:

Information Technology > System Monitoring (1.00)
Information Technology > Architecture > Real Time Systems (1.00)

Applying Machine Learning to Minimize Wireline Formation Testing Failures in Thin Laminated Sands

Fayzullin, Maksim (OMV) | Schmidt, Dennis (OMV) | Deckers, Marie (OMV)

Abstract This paper demonstrates how supervised machine learning (ML) aids planning and acquisition of wireline formation testing (WFT) in thin laminated sands. Available well data was used to train a set of algorithms to identify intervals where tests are likely to fail. The trained model aims to prevent WFT failures what in turn results in reduced rig downtime, increased efficiency of the logging contracts and improved reservoir characterization. Wireline formation testing is essential to acquire rock and fluid characteristics in multilayered reservoirs setting up the base for the upcoming decisions. This becomes significantly complicated in thin laminated sands with a thick hydrocarbon column, requiring hundred(s) of points to meet given objectives. The percentage of failed tests can be much higher than those of being successful. In this context an automated advisory system, based on the abundant historic WFT dataset, can mitigate personal biases of the subsurface team and boost the share of successful tests in future wells. A combined set of wireline logs served as features to predict WFT outcome in two classification approaches. Binary classification predicts likelihood of having a good test or a failure, whereas multi-classification further details failure types into 5 categories. The overall dataset comprised more than 500 points (testing attempts) within the concession to train various ML models, using variety of preprocessing and hyper parameters. Their accuracy and area under curve (AUC) were used as the ranking criteria. The performance mostly depends on the number of classes to be predicted, the number of input features and the number of data points available for training. Less classes to predict and more input features result generally in better model metrics. The final selected model attained a maximum accuracy of 0.75 in two exploration wells in the adjacent concessions, i.e. correctly predicting 75 outcomes out of 100 wireline formation tests. A log interpretation suite accesses the deployed model via a cloud endpoint for the upcoming infill wells. The approach could improve wireline formation testing in other reservoirs or regions prone to WFT failures, where accumulated data is sufficient for machine learning applications. This could result in tangible savings during well operations.

doi: 10.2118/214390-MS

SPE EuropEC - Europe Energy Conference featured at the 84th EAGE Annual Conference & Exhibition

SPE-214390-MS

Country: Europe > Austria (0.28)

Industry: Energy > Oil & Gas > Upstream (1.00)

SPE Disciplines:

Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
Reservoir Description and Dynamics > Formation Evaluation & Management > Open hole/cased hole log analysis (1.00)
Reservoir Description and Dynamics > Formation Evaluation & Management > Formation test analysis (e.g., wireline, LWD) (1.00)
Data Science & Engineering Analytics > Information Management and Systems > Artificial intelligence (1.00)

Technology: Information Technology > Artificial Intelligence > Machine Learning > Performance Analysis > Accuracy (1.00)

Numerical Models for Upscaling of Caprock Properties from Small Sample Laboratory Testing

Cerasi, Pierre Rolf (SINTEF Industry) | Ringstad, Cathrine (SINTEF Industry) | Skorpa, Ragnhild (SINTEF Industry)

Abstract This work had as objective to provide simple numerical models capable of bridging between small sample or cuttings mechanical tests in the laboratory and reservoir-scale models. Numerical models are developed for tests such as the Brazilian indirect tensile test and the direct shear punch test. Intermediately upscaled shale models can be developed to model shale caprock behavior under subsurface storage operations such as CO2 or H2 storage. Of importance to creating a useful material model is to take into account the anisotropic nature of shale caprock, by introducing parallel weak planes in the models. Simulating laboratory tests allows one to tune spacing and properties of such planes with no need for microscopic and detailed accuracy. The effect of weak plane spacing and orientation on the elastic deformation of a layered material is investigated using a simple finite difference scheme. In uniaxial deformation, weakening or hardening is included through a stress-dependent stiffness modulus. Strength dependence on weak plane orientation is modelled using the finite element code DIANA. Tuning of weak plane frequency and stiffness contrast to rock bulk results in stress strain plots where the upscaled stiffness corresponds to simple analytical models. This makes it possible to specify anisotropy parameter inputs for large-scale models. Further tuning to laboratory experiments is possible through the use of the stress-dependent stiffness, making more accurate predictive upscaled models. Similarly, results from tensile strength and shear strength numerical testing highlight the fractures and their interaction with weak planes.

doi: 10.2118/214417-MS

SPE EuropEC - Europe Energy Conference featured at the 84th EAGE Annual Conference & Exhibition

SPE-214417-MS

Country:

North America > United States (0.93)
Europe > Norway (0.69)

Industry: Energy > Oil & Gas > Upstream (1.00)

Oilfield Places:

Europe > Norway > North Sea > Central North Sea > Central Graben > PL 018 > Block 2/7 > Greater Ekofisk Field > Eldfisk Field > Tor Formation (0.99)
Europe > Norway > North Sea > Central North Sea > Central Graben > PL 018 > Block 2/7 > Greater Ekofisk Field > Eldfisk Field > Hod Formation (0.99)
Europe > Norway > North Sea > Central North Sea > Central Graben > PL 018 > Block 2/7 > Greater Ekofisk Field > Eldfisk Field > Ekofisk Formation (0.99)
(32 more...)

SPE Disciplines:

Reservoir Description and Dynamics > Storage Reservoir Engineering > CO2 capture and sequestration (1.00)
Reservoir Description and Dynamics > Reservoir Simulation (1.00)
Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (0.96)
(2 more...)

Technology: Information Technology (0.48)

Smith, Fraser Troy (StimStixx Technologies Inc.) | Hadziavdic, Ina (StimStixx Technologies Inc., RAG Austria AG)

Novel Acid Stimulation Technique for Production Improvement – Austrian Eocene Case Study

Abstract A new approach to acidizing is presented where an inert dry chemical is hermetically sealed inside a metal carrier and deployed downhole via E-line or slickline. The tool is spotted in front of the zone of interest and an exothermic reaction is initiated generating hot acid vapour. A depleted Eocene sandstone reservoir with a 2 7/8″ tubing inside 6 5/8″ casing was successfully treated leading to sustained production enhancement in addition to significant carbon footprint reduction when compared to a conventional treatment. The treatment approach, production results and description of the CO2 reduction is presented. A rigorous well candidate selection process was done as part of the treatment design which analyzed information including damage mechanism, well completion architecture, mineralogy, well deviation, formation type and compatibility. Based on this analysis, the tool type and tool placement sequence were determined to optimize the stimulation. For this well, two 2″ HCl and two 2″ 12:3 HCl/HF tools were used to treat a 5.5 m perforated interval. The HCl tools served as pre-flush treatment and removed any scale. This was followed by 12:3 HCl/HF tools which stimulated the near wellbore matrix and ultimately improved the reservoir fluid influx. After each tool was ignited, a drop in the fluid level was observed. This was positive indication that the acid vapour was enhancing connectivity to the reservoir. When pulled to surface, it was observed that all four tools had ignited and had undergone a complete chemical burn. The well had several tubing and pump changes throughout its long production history. More recently, the well was treated by bullheading EDTA and solvent to re-establish the oil production rate with unsatisfactory long-term production results. Prior to the novel treatment, the well had been producing at 9 – 11 m/d (gross rate) and 1.8 m/d of oil. After the application of the novel technique, the production results showed a return to the historical rate of 1.8 m/d of oil (100% increase). Eighteen months post-treatment, the oil production is sustained and producing between 1.5 - 1.6 m/d. Flow-back equipment was eliminated from the operation since the highly reactive hot acid is fully spent and dissipated. The operation was rigless and the only equipment required was a wireline unit, a crane, and a small fluid truck. The entire stimulation was completed in less than one day and the well could be put immediately back on production. A secondary benefit was a notable reduction in CO2 associated with this treatment method versus a conventional acid treatment. This was achieved by reducing the heavy equipment requirements and the associated diesel consumption.

doi: 10.2118/214416-MS

SPE EuropEC - Europe Energy Conference featured at the 84th EAGE Annual Conference & Exhibition

SPE-214416-MS

Country: Europe > Austria (0.47)

Genre:

Research Report > New Finding (0.34)
Overview (0.34)

Geologic Time: Phanerozoic > Cenozoic > Paleogene > Eocene (0.62)

Industry: Energy > Oil & Gas > Upstream (1.00)

SPE Disciplines:

Well Completion > Acidizing (1.00)
Production and Well Operations > Well Intervention (1.00)
Well Completion > Completion Installation and Operations > Perforating (0.90)
(3 more...)

Investigation of Subsurface Integrity of Depleted Porous Gas Reservoirs for the Purpose of Hydrogen Storage

Andiappan, Anitha (RAG Austria AG) | Pichler, Markus (RAG Austria AG) | Bauer, Stephan (RAG Austria AG)

Abstract Geographical and seasonal differences in the supply and demand of renewable energy is a great challenge for building a sustainable future energy system. One approach is to store renewable energy in the form of hydrogen in existing depleted underground gas reservoirs and retrieve this energy on demand. However, it is unknown if the storage of hydrogen is technologically feasible, specifically if hydrogen can be stored in the same way as natural gas in porous reservoirs and if there are negative impacts on integrity and safety of the surface and subsurface storage facility. To answer these questions, RAG Austria AG has conducted field and laboratory experiments in the past decade. We have injected gas mixtures containing up to 20 volume percent of hydrogen into a depleted porous gas reservoir as part of the field test. First, we evaluated the gas composition, downhole pressure and temperature measurements as well as microbial data from the field test. Our findings suggest changes in the composition of produced gas, however no negative effects on reservoir integrity and no apparent geochemical effects. Next, we investigated the tightness of the caprock against hydrogen intrusion. The experimental results show that the behavior of hydrogen in the sealing materials is similar to that of natural gas. Furthermore, laboratory experiments with pure hydrogen revealed that diffusion effects in reservoir rocks can be neglected for the timeframe of seasonal gas storage. Taken together, these first results indicate that storage of hydrogen in depleted porous gas reservoirs could be a way forward to have hydrogen as a more reliable and versatile energy carrier. Still, we need to gain more insights regarding safety and technical feasibility for the underground storage of pure hydrogen. To address this, RAG Austria AG will start an unprecedented field test with pure hydrogen in a porous depleted gas reservoir in 2023.

doi: 10.2118/214432-MS

SPE EuropEC - Europe Energy Conference featured at the 84th EAGE Annual Conference & Exhibition

SPE-214432-MS

Country: Europe > Austria > Upper Austria (0.16)

Genre: Research Report > New Finding (1.00)

Geologic Time: Phanerozoic > Cenozoic (0.47)

Geophysics: Geophysics > Seismic Surveying (0.46)

Industry: Energy > Oil & Gas > Upstream (1.00)

Oilfield Places:

Europe > Austria > Upper Austria > Molasse Basin (0.99)
Europe > Austria > Lower Austria > Molasse Basin (0.99)

SPE Disciplines:

Reservoir Description and Dynamics > Storage Reservoir Engineering > Natural gas storage (1.00)
Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
Reservoir Description and Dynamics > Improved and Enhanced Recovery (1.00)
(2 more...)

Fluid Identification from Mud Gas in the Overburden – A Case Study for the Snorre Field

Abstract Based on the successful utilization of advanced mud gas (AMG) for fluid identification in five production/injection wells in the Snorre field, the fluid identification while drilling technology was deployed for a seismic anomaly within the overburden at the Kyrre formation level. The main objective was to identify the reservoir fluid type (oil versus gas) within the anomaly and to use this information to potentially de-risk a similar shallower seismic anomaly - the Linga prospect at the top Shetland level. Fluid identification while drilling is an award-winning innovation that has been broadly used in exploration and production wells at Equinor. The digital technology combines mud gas and PVT data for accurate reservoir fluid typing and property predictions. Snorre field is one of the first users of the technology and accumulated good experiences regarding the capacity and limitations in reservoir zones. Due to the lack of other good tools to identify the hydrocarbon in overburden in a cost-efficient manner, the Snorre field decided to deploy the fluid identification technology for the task. Utilizing AMG data in the overburden for the four Snorre Expansion Project (SEP) wells showed satisfactory results. Reservoir oil was identified with confidence in the Kyrre formation for the first three wells, and no additional logging was necessary. The 4th well was drilled with higher ROP (above 30 m/hr) and proved a similar oil signature without compromising the data quality. The main objective was met, the fluid type in the Kyrre anomaly was confirmed, and this result was a de-risked Linga prospect. The probability of producing the Linga prospect has increased due to the accurate reservoir fluid type. The experiences in the overburden from the Snorre field show fluid identification from mud gas is a cost-efficient tool and has the potential to be utilized broadly in the overburden. With an accurate fluid identification in the overburden, we can achieve safety assurance, reduced drilling costs, and matured production prospects.

doi: 10.2118/214440-MS

SPE EuropEC - Europe Energy Conference featured at the 84th EAGE Annual Conference & Exhibition

SPE-214440-MS

Country: Europe > Norway > North Sea > Northern North Sea (1.00)

Genre: Research Report (0.68)

Geologic Time: Phanerozoic > Mesozoic (1.00)

Geophysics: Geophysics > Seismic Surveying (1.00)

Industry: Energy > Oil & Gas > Upstream (1.00)

Oilfield Places:

Europe > United Kingdom > North Sea > North Sea Basin (0.99)
Europe > Norway > North Sea > Northern North Sea > East Shetland Basin > Tampen Area (0.99)
Europe > Norway > North Sea > Northern North Sea > East Shetland Basin > PL 375 > Block 34/7 > Snorre Field > Statfjord Group (0.99)
(22 more...)

SPE Disciplines:

Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
Reservoir Description and Dynamics > Fluid Characterization (1.00)
Data Science & Engineering Analytics > Information Management and Systems (1.00)

Technology: Information Technology > Artificial Intelligence > Machine Learning (1.00)

Olszowska, Daria (The University of Texas at Austin) | Gallardo-Giozza, Gabriel (The University of Texas at Austin) | Crisafulli, Domenico (The University of Texas at Austin) | Torres-Verdín, Carlos (The University of Texas at Austin)

Angle-Dependent Ultrasonic Wave Reflection for Estimating High-Resolution Elastic Properties of Complex Rock Samples

Abstract Due to depositional, diagenetic, and structural processes, reservoir rocks are rarely homogeneous, often exhibiting significant short-range variations in elastic properties. Such spatial variability can have measurable effects on macroscopic mechanical properties for drilling and fluid production operations. We describe a new laboratory method for the acquisition of ultrasonic angle-dependent measurements of reflected waves that delivers high-resolution, continuous descriptions of P- and S-wave velocity along the surface of the rock sample. Reflection coefficient vs. incidence angle is the main source of information about rock elastic properties. The acquired measurements are matched to numerical simulations to estimate P- and S-wave velocity and density of the porous sample and their variations within the rock specimen, hence providing continuous descriptions of sample complexity. Data collected from various locations on the rock specimen are subsequently used to construct two-dimensional (2D) models of elastic properties along the surface of the rock sample. P- and S-wave velocities estimated with this method agree well with acoustic transmission measurements for most homogeneous rocks. The spatial resolution of the method is limited by receiver size, measurement frequency, and incidence angle. At high incidence angles, the surface area sensitive to the measurements increases, and consequently, the spatial resolution of the corresponding reflection coefficient decreases across neighboring rock features.

doi: 10.30632/PJV64N3-2023a6

SPWLA

SPWLA-2023-v64n3a6

Petrophysics

Country:

Europe (1.00)
North America > United States > Texas > Travis County > Austin (0.28)

Genre: Personal > Honors (1.00)

Geophysics:

Geophysics > Seismic Surveying > Seismic Processing (0.89)
Geophysics > Seismic Surveying > Seismic Modeling (0.68)

Industry: Energy > Oil & Gas > Upstream (1.00)

Oilfield Places: North America > United States > Gulf of Mexico > Central GOM > East Gulf Coast Tertiary Basin > Mississippi Canyon > Block 522 > Na Kika Project > Fourier Field (0.97)

SPE Disciplines:

Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (1.00)
Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)

Technology: Information Technology (1.00)

Shale Characterization Using T1-T2* Magnetic Resonance Relaxation Correlation Measurement at Low and High Magnetic Fields

Zamiri, Mohammad Sadegh (University of New Brunswick) | Guo, Jiangfeng (University of New Brunswick) | Marica, Florea (University of New Brunswick) | Romero-Zerón, Laura (China University of Petroleum (Beijing)) | Balcom, Bruce J. (University of New Brunswick)

Abstract Shale characterization is complicated by low porosity and low permeability. Nano-porosity and a high degree of heterogeneity present further difficulties. H magnetic resonance (MR) methods have great potential to provide quantitative and spatially resolved information on fluids present in porous rocks. The shale MR response, however, is challenging to interpret due to short-lived signals that complicate quantitative signal detection and imaging. Multicomponent signals require high-resolution methods for adequate signal differentiation. MR methods must cope with low measurement sensitivity at low field. In this paper, T1-T2* and Look-Locker T1*-T2* methods were employed to resolve the shale signal for water, oil, and kerogen at high and low field. This permits fluid quantification and kerogen assessment. The T1-T2* measurement was employed to understand and control contrast in the single-point ramped imaging with T1 enhancement (SPRITE) imaging method. This permitted imaging that gave separate images of water and oil. Water absorption/desorption, evaporation, step pyrolysis, and water uptake experiments were monitored using T1-T2* measurement and MR imaging. The results showed (i) the capability of the T1-T2* measurement to differentiate and quantify kerogen, oil, and water in shales, (ii) the characterization of shale heterogeneity on the core plug scale, and (iii) demonstrated the key role of wettability in determining the spatial distribution of water in shales.

doi: 10.30632/PJV64N3-2023a5

SPWLA

SPWLA-2023-v64n3a5

Petrophysics

Country:

North America > United States > Texas (0.93)
North America > Canada (0.93)
Europe (0.93)

Genre: Research Report > New Finding (0.48)

Industry: Energy > Oil & Gas > Upstream (1.00)

Oilfield Places:

North America > United States > West Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
North America > United States > West Virginia > Appalachian Basin > Marcellus Field > Marcellus Shale Formation (0.99)
North America > United States > Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
(14 more...)

SPE Disciplines:

Reservoir Description and Dynamics > Unconventional and Complex Reservoirs > Shale oil (1.00)
Reservoir Description and Dynamics > Unconventional and Complex Reservoirs > Shale gas (1.00)
Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
Reservoir Description and Dynamics > Formation Evaluation & Management (1.00)

Technology: Information Technology > Sensing and Signal Processing > Image Processing (0.46)